/*
 * Copyright (C) 2008 by Xume.
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.xume.critann.handler;

import java.lang.annotation.Annotation;

import org.xume.critann.InvalidCriteriaBeanConfigurationException;
import org.xume.critann.annotations.projection.ProjectionCallbackClass;
import org.xume.critann.callback.AnnotationCallback;
import org.xume.critann.callback.ClassAnnotationCallback;

/**
 * $Id: ProjectionAnnotationHandler.java 17 2008-10-12 11:36:05Z johan.siebens $
 * 
 * @author Johan Siebens
 */
public class ProjectionAnnotationHandler extends AnnotationHandler {

	private boolean found = false;

	@Override
	public boolean supports(Annotation annotation) {
		return annotation.annotationType().getAnnotation(ProjectionCallbackClass.class) != null;
	}

	@Override
	@SuppressWarnings("unchecked")
	public AnnotationCallback handleAnnotation(Class<?> criteriaBeanClass, Annotation annotation) throws Exception {
		if (found) {
			throw new InvalidCriteriaBeanConfigurationException(criteriaBeanClass, "Multiple Projection annotations found.");
		}
		ProjectionCallbackClass callbackClass = annotation.annotationType().getAnnotation(ProjectionCallbackClass.class);
		ClassAnnotationCallback callback = callbackClass.value().newInstance();
		callback.initialize(criteriaBeanClass, annotation);
		found = true;
		return callback;
	}

}
